How to disassemble Xiaomi 4X: a step-by-step repair guide

Disassembling the Xiaomi Redmi 4X (codename: santoni) is a process that requires care, patience and understanding of the architecture of modern mobile devices. Although it was released several years ago, it is still popular because of its reliability, but the physical wear of components is inevitable: screens break, batteries lose capacity, and charging connectors fail, which gives the owner a choice: carry the device into service or try to repair with their hands.

Before you start dismantling, it's important to be aware of the risks. Opening the case automatically deprives you of warranty if it's still in place, and careless movement can damage the plumes or break the back cover. However, if you're ready to work with small screws and thin plumes, this article will be your main guide. We'll look in detail at how to safely remove the back panel, disable the battery and replace the main modules without turning the smartphone into a pile of spare parts.

Preparation of the workplace and necessary tools

Quality repairs begin long before you touch the first screw. You need to organize a space where nothing is distracting and small details are not lost in the dust. The light must be bright and directed so that you can see microscopic screws and connectors. Inadequate lighting often causes craftsmen to lose screws or tear plumes without noticing their thinning.

To work with Xiaomi Redmi 4X, you will need a specific set of tools that differ from the standard set for PC. The basis is a set of precision screwdrivers, since this model uses screws of different standards. It is also critical to have a suction cup or a thin plastic blade to work with the adhesive layer. Metal tools are not recommended for opening the case, as they can break the glass or damage antenna inserts.

Here is a list of what to put on your desk before starting the procedure:

• 🔧 Screwdriver Set (Phillips #000 and Flat)
• 📱 Plastic spatula (mediator) or thin knife
• 🌬️ Dryer or heat pad (to heat glue)
• 🧲 Magnetic mat or organizer for screws
• 🔦 Powerful lamp or magnifying glass

Pay special attention to the cleanliness of the surface. Dust trapped under the display module or inside the housing can cause "dead spots" on the screen or close contacts. Static electricity also poses a threat to the motherboard, so it is recommended to work in antistatic gloves or at least periodically touch the grounded metal object to relieve charge.

Removal of the back cover and primary dismantling

The Redmi 4X has a Unibody all-metal body, but the back cover here is not a load-bearing structure in the classical sense, it is glued around the perimeter. It is the first barrier to overcome. Heat is a key step: the adhesive used by Xiaomi at room temperature holds very tightly, but softens at a temperature of about 60-70 degrees Celsius.

Turn on the dryer at medium power and evenly warm the perimeter of the back cover for 2-3 minutes. Do not keep the hot air flow at one point for too long so as not to damage the display on the back side or overheat the battery. After heating, insert the plastic card or spatula into the upper corner where the speaker is usually located, and carefully guide the tool along the faces, cutting the adhesive layer.

⚠️ Warning: Do not try to lid the lid near the Home button or the camera, there are plumes that can be easily broken by careless movement.

Once the lid is removed, you'll see the inside of the lid, and you'll see a plastic pad covering the main components, and it's locked with several screws that you need to unscrew. Be careful, the screws may be of different lengths, and if you confuse them when you build them, you can damage the thread or punch the board with a screw point, and marking the screws on the magnetic mat will help avoid confusion.

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Use tape to glue the removed back cover to the table with the outside down – this will prevent it from falling and scratching the glossy surface during operation.

Battery shutdown and motherboard protection

The golden rule of any electronics repair is to turn off the power first. In the case of the Xiaomi 4X smartphone, this means disconnecting the battery plume from the motherboard. Even if the device is turned off, there is residual current on the board, which can lead to a short circuit if metal parts of the tool accidentally contact the components.

Remove the plastic safety plate that covers the connectors. It's usually held on 4-6 screws around the perimeter. Once the protection is removed, you'll see the main battery plume that comes to the board from the bottom or side. Carefully tuck the connector with a plastic blade or nail as you move from the bottom up. Don't pull the wires because they can come off the connector itself.

Here are the main components that will be available after the removal of protection:

• 🔋 Main battery connector
• 📡 Antenna cable (often goes through the entire fee)
• 📷 Main and front camera plumes
• 🖥 Display module plume

After the battery is turned off, it is recommended to wait 10-15 seconds before any further manipulations. This is the time it takes for the capacitors on the board to completely discharge. If you plan to replace the screen, the next step is to turn off the display plume. It is usually fixed with a metal bracket that needs to be carefully bent or unscrewed if it is pressed by a screw.

Replacement of the display module and touch screen

The most common reason for disassembling Xiaomi Redmi 4X is a broken screen. In this model, the display module is a single design, where the glass (touchscreen) and matrix (image) are glued together in the factory. Changing them separately at home is extremely difficult and requires special equipment to remove old glue (separator) and apply new (OCA glue), so we are considering replacing the module in the assembly.

To remove the old module, you need to twist all the screws around the perimeter of the metal frame. Their number can reach 10-12 pieces. After removing the screws, the frame can still hold on to the glue. Carefully warm up the front of the phone with a hairdryer (through the glass if it is whole, or directly along the frame) to soften the glue that holds the module.

Comparison table of modules for Redmi 4X:

When installing a new module, make sure that there are no shards of old glass or glue left on the frame that could create a skew.The new module often comes with an already applied adhesive layer, a closed protective film. Take the film off just before installation and press the module tightly to the frame around the perimeter. Connect the display plume to the final fixation of the screws to check the performance of the image.

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Buying a module assembled with a frame greatly simplifies repair, since you do not need to move the speaker, vibrator and button plumes from the old broken screen to the new one.

Dismantling of battery and power system

Replacing the battery in Xiaomi Redmi 4X is a procedure that requires special care because of the risk of fire of the lithium polymer battery. The battery in this model is glued to the inside of the case quite firmly. Do not try to tamper with the battery with a screwdriver or a metal tool - a puncture of the shell is guaranteed to cause ignition.

To safely extract, use heating and mechanical detachment. Heat the back of the case (or the inside if the case is already open) with a hairdryer to 50-60 degrees. This will soften the glue. Then use a plastic card to slowly and progressively separate the battery from the case, working across the entire area of the element, rather than from one edge.

Important nuances of working with the battery:

• 🚫 Do not bend or deform the battery body
• 🔥 Avoid overheating above 70 degrees Celsius
• 🧤 Work with gloves so as not to contaminate contacts with fat

The new battery should be warmed up a little before installation and a thin layer of B-7000 glue or double-sided phone tape on the back of the battery, which will prevent the battery from bolting inside the case and the plume from drifting away when falling, and make sure that the battery connector sits tightly in the connector and is fixed with a clamping bar.

⚠️ Warning: If you damage the battery shell during the recovery process and smell a sharp chemical smell or smoke, immediately stop working, take the device out into the open space and fill it with sand or place it in a container of water.

Device assembly and initial start

The final stage of dismantling Xiaomi 4X is the assembly, which is done in reverse order. However, there are some nuances. The main thing is not to forget to connect all the plumes before you turn the final screws. Often, the assembled phone does not turn on, and you have to disassemble it again because of a forgotten connector.

First, put all the internal components in place: vibrator, main speaker, charger (if it was removed). Make sure that the antenna cable is properly stacked in its channels and snapped into the connectors, otherwise the phone will not catch the network or Wi-Fi. Then connect the plume of the display and battery.

The sequence of actions during assembly:

1. Connect the display plume and fasten the clamping bracket.
2. Connect the battery plume.
3. Turn on the phone without twisting the screws to check the functionality.
4. Turn off the phone, turn off the battery.
5. Twisting all screws of the frame and installing a plastic lining.
6. Apply glue on the perimeter of the back cover and press it.

After turning on the device, take your time to stick the security glass or put the phone in a case. Leave it on charge for 1-2 hours and watch the heating. If the phone is warming in the area of the processor or battery at rest, you may have screwed the board poorly or damaged some element. In normal mode, the device should remain cold or slightly warm.

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